/*!
* CrossSlide jQuery plugin v0.6.2
*
* Copyright 2007-2010 by Tobia Conforto <tobia.conforto@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
/* Changelog:
*
* 0.6.2 2010-09-29 Added support for rel attribute
* 0.6.1 2010-08-02 Bugfixes
* 0.6 2010-07-03 Variant Ken Burns effect
* 0.5 2010-06-13 Support for animation control and event callbacks
* 0.4.2 2010-06-07 Bugfix
* 0.4.1 2010-06-04 Added target option
* 0.4 2010-05-20 Better error reporting, published on GitHub
* 0.3.7 2009-05-14 Fixed bug when container div's CSS position is not set
* 0.3.6 2009-04-16 Added alt option
* 0.3.5 2009-03-12 Fixed usage of href parameter in 'Ken Burns' mode
* 0.3.4 2009-03-12 Added shuffle option,
* contrib. by Ralf Santbergen <ralf_santbergen@hotmail.com>
* 0.3.3 2008-12-14 Added onclick option
* 0.3.2 2008-11-11 Fixed CSS bugs, contrib. by Erwin Bot <info@ixgcms.nl>
* 0.3.1 2008-11-11 Better error messages
* 0.3 2008-10-22 Option to repeat the animation a fixed number of times
* 0.2 2008-10-15 Linkable images, contrib. by Tim Rainey <tim@zmlabs.com>
* 0.1.1 2008-09-18 Compatibility with prototype.js
* 0.1 2008-08-21 Re-released under GPL v2
* 0.1 2007-08-19 Initial release
*/

(function() {
var $ = jQuery,
animate = ($.fn.startAnimation ? 'startAnimation' : 'animate'),
pause_missing = 'pause plugin missing.';

// utility to format a string with {0}, {1}... placeholders
function format(str) {
for (var i = 1; i < arguments.length; i++)
str = str.replace(new RegExp('\\{' + (i-1) + '}', 'g'), arguments[i]);
return str;
}

// utility to abort with a message to the error console
function abort() {
arguments[0] = 'CrossSlide: ' + arguments[0];
throw new Error(format.apply(null, arguments));
}

// utility to parse "from" and "to" parameters
function parse_position_param(param) {
var zoom = 1;
var tokens = param.replace(/^\s*|\s*$/g, '').split(/\s+/);
if (tokens.length > 3) throw new Error();
if (tokens[0] == 'center')
if (tokens.length == 1)
tokens = ['center', 'center'];
else if (tokens.length == 2 && tokens[1].match(/^[\d.]+x$/i))
tokens = ['center', 'center', tokens[1]];
if (tokens.length == 3)
zoom = parseFloat(tokens[2].match(/^([\d.]+)x$/i)[1]);
var pos = tokens[0] + ' ' + tokens[1];
if (pos == 'left top' || pos == 'top left')
return { xrel: 0, yrel: 0, zoom: zoom };
if (pos == 'left center' || pos == 'center left')
return { xrel: 0, yrel: .5, zoom: zoom };
if (pos == 'left bottom' || pos == 'bottom left')
return { xrel: 0, yrel: 1, zoom: zoom };
if (pos == 'center top' || pos == 'top center')
return { xrel: .5, yrel: 0, zoom: zoom };
if (pos == 'center center')
return { xrel: .5, yrel: .5, zoom: zoom };
if (pos == 'center bottom' || pos == 'bottom center')
return { xrel: .5, yrel: 1, zoom: zoom };
if (pos == 'right top' || pos == 'top right')
return { xrel: 1, yrel: 0, zoom: zoom };
if (pos == 'right center' || pos == 'center right')
return { xrel: 1, yrel: .5, zoom: zoom };
if (pos == 'right bottom' || pos == 'bottom right')
return { xrel: 1, yrel: 1, zoom: zoom };
return {
xrel: parseInt(tokens[0].match(/^(\d+)%$/)[1]) / 100,
yrel: parseInt(tokens[1].match(/^(\d+)%$/)[1]) / 100,
zoom: zoom
};
}

$.fn.crossSlide = function(opts, plan, callback)
{
var self = this,
self_width = this.width(),
self_height = this.height();

// must be called on exactly 1 element
if (self.length != 1)
abort('crossSlide() must be called on exactly 1 element')

// saving params for crossSlide.restart
self.get(0).crossSlideArgs = [ opts, plan, callback ];

// make working copy of plan
plan = $.map(plan, function(p) {
return $.extend({}, p);
});

// options with default values
if (! opts.easing)
opts.easing = opts.variant ? 'swing' : 'linear';
if (! callback)
callback = function() {};

// first preload all the images, while getting their actual width and height
(function(proceed) {

var n_loaded = 0;
function loop(i, img) {
// this loop is a for (i = 0; i < plan.length; i++)
// with independent var i, img (for the onload closures)
img.onload = function(e) {
n_loaded++;
plan[i].width = img.width;
plan[i].height = img.height;
if (n_loaded == plan.length)
proceed();
}
img.src = plan[i].src;
if (i + 1 < plan.length)
loop(i + 1, new Image());
}
loop(0, new Image());

})(function() { // then proceed

// check global params
if (! opts.fade)
abort('missing fade parameter.');
if (opts.speed && opts.sleep)
abort('you cannot set both speed and sleep at the same time.');

// conversion from sec to ms; from px/sec to px/ms
var fade_ms = Math.round(opts.fade * 1000);
if (opts.sleep)
var sleep = Math.round(opts.sleep * 1000);
if (opts.speed)
var speed = opts.speed / 1000,
fade_px = Math.round(fade_ms * speed);

// set container css
self.empty().css({
overflow: 'hidden',
padding: 0
});
if (! /^(absolute|relative|fixed)$/.test(self.css('position')))
self.css({ position: 'relative' });
if (! self.width() || ! self.height())
abort('container element does not have its own width and height');

// random sorting
if (opts.shuffle)
plan.sort(function() {
return Math.random() - 0.5;
});

// prepare each image
for (var i = 0; i < plan.length; ++i) {

var p = plan[i];
if (! p.src)
abort('missing src parameter in picture {0}.', i + 1);

if (speed) { // speed/dir mode

// check parameters and translate speed/dir mode into full mode
// (from/to/time)
switch (p.dir) {
case 'up':
p.from = { xrel: .5, yrel: 0, zoom: 1 };
p.to = { xrel: .5, yrel: 1, zoom: 1 };
var slide_px = p.height - self_height - 2 * fade_px;
break;
case 'down':
p.from = { xrel: .5, yrel: 1, zoom: 1 };
p.to = { xrel: .5, yrel: 0, zoom: 1 };
var slide_px = p.height - self_height - 2 * fade_px;
break;
case 'left':
p.from = { xrel: 0, yrel: .5, zoom: 1 };
p.to = { xrel: 1, yrel: .5, zoom: 1 };
var slide_px = p.width - self_width - 2 * fade_px;
break;
case 'right':
p.from = { xrel: 1, yrel: .5, zoom: 1 };
p.to = { xrel: 0, yrel: .5, zoom: 1 };
var slide_px = p.width - self_width - 2 * fade_px;
break;
default:
abort('missing or malformed dir parameter in picture {0}.', i+1);
}
if (slide_px <= 0)
abort('impossible animation: either picture {0} is too small or '
+ 'div is too large or fade duration too long.', i + 1);
p.time_ms = Math.round(slide_px / speed);

} else if (! sleep) { // full mode

// check and parse parameters
if (! p.from || ! p.to || ! p.time)
abort('missing either speed/sleep option, or from/to/time params '
+ 'in picture {0}.', i + 1);
try {
p.from = parse_position_param(p.from)
} catch (e) {
abort('malformed "from" parameter in picture {0}.', i + 1);
}
try {
p.to = parse_position_param(p.to)
} catch (e) {
abort('malformed "to" parameter in picture {0}.', i + 1);
}
if (! p.time)
abort('missing "time" parameter in picture {0}.', i + 1);
p.time_ms = Math.round(p.time * 1000)
}

// precalculate left/top/width/height bounding values
if (p.from)
$.each([ p.from, p.to ], function(i, each) {
each.width = Math.round(p.width * each.zoom);
each.height = Math.round(p.height * each.zoom);
each.left = Math.round((self_width - each.width) * each.xrel);
each.top = Math.round((self_height - each.height) * each.yrel);
});

// append the image (or anchor) element to the container
var img, elm;
elm = img = $(format('<img src="{0}"/>', p.src));
if (p.href)
elm = $(format('<a href="{0}"></a>', p.href)).append(img);
if (p.onclick)
elm.click(p.onclick);
if (p.alt)
img.attr('alt', p.alt);
if (p.rel)
elm.attr('rel', p.rel);
if (p.href && p.target)
elm.attr('target', p.target);
elm.appendTo(self);
}
delete speed; // speed mode has now been translated to full mode

// utility to compute the css for a given phase between p.from and p.to
// 0: begin fade-in, 1: end fade-in, 2: begin fade-out, 3: end fade-out
function position_to_css(p, phase) {
var pos = [ 0, fade_ms / (p.time_ms + 2 * fade_ms),
1 - fade_ms / (p.time_ms + 2 * fade_ms), 1 ][phase];
return {
left: Math.round(p.from.left + pos * (p.to.left - p.from.left)),
top: Math.round(p.from.top + pos * (p.to.top - p.from.top)),
width: Math.round(p.from.width + pos * (p.to.width - p.from.width)),
height: Math.round(p.from.height + pos * (p.to.height-p.from.height))
};
}

// find images to animate and set initial css attributes
var imgs = self.find('img').css({
position: 'absolute',
visibility: 'hidden',
top: 0,
left: 0,
border: 0
});

// show first image
imgs.eq(0).css({ visibility: 'visible' });
if (! sleep)
imgs.eq(0).css(position_to_css(plan[0], opts.variant ? 0 : 1));

// create animation chain
var countdown = opts.loop;
function create_chain(i, chainf) {
// building the chain backwards, or inside out

if (i % 2 == 0) {
if (sleep) {
// single image sleep
var i_sleep = i / 2,
i_hide = (i_sleep - 1 + plan.length) % plan.length,
img_sleep = imgs.eq(i_sleep),
img_hide = imgs.eq(i_hide);
var newf = function() {
callback(i_sleep, img_sleep.get(0));
img_hide.css('visibility', 'hidden');
setTimeout(chainf, sleep);
};
} else {
// single image animation
var i_slide = i / 2,
i_hide = (i_slide - 1 + plan.length) % plan.length,
img_slide = imgs.eq(i_slide),
img_hide = imgs.eq(i_hide),
time = plan[i_slide].time_ms,
slide_anim = position_to_css(plan[i_slide],
opts.variant ? 3 : 2);
var newf = function() {
callback(i_slide, img_slide.get(0));
img_hide.css('visibility', 'hidden');
img_slide[animate](slide_anim, time, opts.easing, chainf);
};
}
} else {
// double image animation
var i_from = Math.floor(i / 2),
i_to = Math.ceil(i / 2) % plan.length,
img_from = imgs.eq(i_from),
img_to = imgs.eq(i_to),
from_anim = {},
to_init = { visibility: 'visible' },
to_anim = {};
if (i_to > i_from) {
to_init.opacity = 0;
to_anim.opacity = 1;
if (opts.doubleFade)
from_anim.opacity = 0;
} else {
from_anim.opacity = 0;
if (opts.doubleFade) {
to_init.opacity = 0;
to_anim.opacity = 1;
}
}
if (! sleep) {
// moving images
$.extend(to_init, position_to_css(plan[i_to], 0));
if (! opts.variant) {
$.extend(from_anim, position_to_css(plan[i_from], 3));
$.extend(to_anim, position_to_css(plan[i_to], 1));
}
}
if ($.isEmptyObject(to_anim)) {
var newf = function() {
callback(i_to, img_to.get(0), i_from, img_from.get(0));
img_to.css(to_init);
img_from[animate](from_anim, fade_ms, 'linear', chainf);
};
} else if ($.isEmptyObject(from_anim)) {
var newf = function() {
callback(i_to, img_to.get(0), i_from, img_from.get(0));
img_to.css(to_init);
img_to[animate](to_anim, fade_ms, 'linear', chainf);
};
} else {
var newf = function() {
callback(i_to, img_to.get(0), i_from, img_from.get(0));
img_to.css(to_init);
img_to[animate](to_anim, fade_ms, 'linear');
img_from[animate](from_anim, fade_ms, 'linear', chainf);
};
}
}

// if the loop option was requested, push a countdown check
if (opts.loop && i == plan.length * 2 - 2) {
var newf_orig = newf;
newf = function() {
if (--countdown) newf_orig();
}
}

if (i > 0)
return create_chain(i - 1, newf);
else
return newf;
}
var animation = create_chain(plan.length * 2 - 1,
function() { return animation(); });

// start animation
animation();
});
return self;
};

$.fn.crossSlideFreeze = function()
{
this.find('img').stop();
}

$.fn.crossSlideStop = function()
{
this.find('img').stop().remove();
}

$.fn.crossSlideRestart = function()
{
this.find('img').stop().remove();
$.fn.crossSlide.apply(this, this.get(0).crossSlideArgs);
}

$.fn.crossSlidePause = function()
{
if (! $.fn.pause)
abort(pause_missing);
this.find('img').pause();
}

$.fn.crossSlideResume = function()
{
if (! $.fn.pause)
abort(pause_missing);
this.find('img').resume();
}
})();